On Jun 3, Tomasz Skutnik wrote:
>> Thanks for clarification Eli. That expanded my understanding of the
> naming problem. However, as I see it, the main issue is not with
> error reporting during bug hunt (where "more correct" name is
> desirable). It's about signaling of missing keyword parameters on
> function invocation - which IMHO is rather common programming
> mistake.
Well, if you do what I suggested:
> > #lang scheme
> > (provide make-foo)
> > (define-struct internal-foo (x y z))
> > (define (make-foo ...) ... make-internal-foo ...)
then the error reports *will* talk about `make-foo'.
> For me, the best option would be using procedure-rename, if it would
> retain keyword parameters. [...]
I think that the purpose of `procedure-rename' is unclear in this
thread. Its intention is as a tool where the name is determined at
run-time -- if you want to use a different name for your function
definition, then this was always possible. Here's an easy way to do
it:
(define foo (let ([bar (lambda (x) x)]) bar))
or a possibly more convenient form:
(define foo
(let ()
(define (bar x) x)
bar))
and it's easy to make a macro out of all of this:
(define-syntax-rule (define/renamed external-name (internal-name . args)
body ...)
(define internal-name
(let ()
(define (external-name . args) body ...)
external-name)))
or even directly provide the renamed version, and skip the internal
name completely (making it inaccessible within the defining module):
(define-syntax-rule (define/provide (external-name . args)
body ...)
(begin
(define hidden-name
(let ()
(define (external-name . args) body ...)
external-name))
(provide (rename-out [hidden-name external-name]))))
--
((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay:
http://www.barzilay.org/ Maze is Life!